Walsingham

Walsingham was, and is, a pilgrimage site.  Having been told by the Virgin Mary in the Holy Land to build a replica of the house where the Annunciation occurred, Richeldis de Faverches built a small wooden house in the middle of Norfolk.  This soon became a centre for pilgrimage, and the Augustinian canons moved in and built a fine priory there in 1153 (Augustinians were in charge of several pilgrimage sites - e.g. St Frideswide's, Oxford).

The seal is late 12th or early 13th century.  It's very nice - with the BVM & C on a lovely high-backed throne and these gorgeous drapes making almost a polylobed recessed panel.

The obverse is a church with people (pilgrims?) praying in.

Recently, the V&A's Langham Madonna was shown to be a good candidate for the famed statue of Our Lady of Walsingham.

PS.  I've just seen Kirkstall's first seal.  It's very similar - a copy, one might say.

Oseney

Oseney Abbey's seal is from c.1290, and has the BVM and Child, she crowned (fleur-de-lis); he nimbed (cruciform).  She seems to be giving him a dummy; Birch says it's an orb (could it be a rose?).  Is Christ receiving the nice ball from mama, or is his r-h in benediction? 

Cf the amazing Clare Chasuble (below, courtesy of the V&A); you can read more about it here and on this nice post about Opus Anglicanum.  It's from about the same time, celebrating the marriage of Margaret de Clare and Edmund, nephew of Henry III.  (They were married in 1272 and divorced in 1294.)

(My money's on Bogo de Clare for commissioning the chasuble - Lars Kjaer's exploration of his household accounts show that's exactly the sort of thing he'd go for!  By the way, notice the BVM's seat - very like the Merton one.)
 

On the Oseney seal, Mother and Child sit in a trefoiled arch, with lovely crockets (the things that look like snails crawling up a spire), with buttresses and pinnacles.  Birch notes the inscription De Oxonia on the plinth of the niche.  They are on top of a platform with two architectural corbels, all being a canopy for an ox passant guardant, for Oxford.  The presence of the ox is interesting; Oseney was a major landlord in Oxford, but also had more to do with its university than is generally acknowledged.

The seal has certain similarities with Bruton's, which itself has similarities with Merton's.

Bruton

H. Kingsford pointed out the similarity between Merton's seal and that of Bruton Priory, Somerset.

Left is Bruton's seal and right is Merton's.  Merton's, from 1241, has finer workmanship, and it's likely that Bruton's was a copy, or derived inspiration from Merton's.  I think that Merton's was the inspiration for a number of seals, including that of Nicholas Farnham, Bishop of Durham.  In 1241, Merton was at the height of its powers, being used for royal administration, and being a centre for learning.

The similarities are the Virgin and Child, although she does not hold the virga; the 'windows' with canons' head peeking through; the canopy over the BVM and Child, even with the little rosettes in between the spires.  Her throne is different, and it rests on another canopy, under which are canons praying to her.  On either side of her, above the panels, are a star and moon.  Both the star and moon and the praying figures are fashionable features, and can be seen on various institutional and episcopal seals from the period.  No one seems to have made a comprehensive study of these...yet... but I'm working on it!  It's impossible to say whether the Bruton seal was from the same workshop, or was a provincial copy.  Bruton was nowhere near as wealthy as Merton, and Merton's seal must have cost a lot.  I think Kingsford must be right that Merton's seal was made in the workshop that supplied King Henry's seal(s).  Could Bruton have afforded a seal by the king's workshop?  On the other hand, the Bruton seal is also very fine (I'll try to get a better picture of both seals soon).  Perhaps someone was related to someone.