Newest Catalogue Value Question

Here's a Queston I've never asked: What is the current catalogue value of these three Overprint errors? I can't seem to find an online catalogue source.
O25Sa
O35Sa ex Markovits (sp?) (his 2nd copy)
O57Sa
Thank you for your help.

O25Sa = $2500

O35Sa = $2750

O57Sa = $2500

Thank you rogdcam.
May as well be a total pest..

In May of 2006, the Chronicle published "Combs' Broken C at Position 28: Conformation of a Constant
Overprint Variety of the Specimen Second Printing by Alfred E. Staubus and George G. Sayers.

https://chronicle.uspcs.org/pdf/Chr...10/12755.pdf


Has this variety ever been given a number and or a value?


Edit for a partial answer,
The first printing error SEPCIMEN is cataloged with the addition of a lower case a as l listed in my first post.
The second printing on Horzontally ribbed paper is cataloged with the addition of a lower case b.
The long cataloged variety "small dotted i" is noted with the addition of a lower case c.
As listed in my old 2014 Specialized.

Has not changed as of 2021 for sure, and I don't remember seeing any other differences in the later catalogs.

Very scarce stamps especially if sound. Rarely come up for sale.

Quite true. The 3 SEPCIMEN errors above were all auction buys.
But I am thinking of putting them up on ebay, as I stopped collecting these years ago, will surly help fund the RPO collection.
The four broken Cs were all un -noted, nothing noted about their true identity, Got them off ebay, back when we knew who we were bidding against. Around 2000. Won all 4 as the only bidder!
Yes! I was thrilled when I read the above-mentioned Chronicle article. After I read the Combs booklet mentioned in the Staubus & Sayers article!!

They are not listed in the 2024 Specialized.