Maybe just testing to the water to see what interest there is in both as a pair (not selling individually) and are happy to discuss any reasonable offers. I don't know what the two are 'worth' and its not as if you will find 2 genuine Custom 24's with the exact same serial number....
Having seen some coins with a 'mistake' selling for a LOT more than face value to a collector, maybe to the right person, these maybe worth a lot - especially if they are looking for a long term investment. It does seem that guitars from this era of PRS are going up in value. To someone looking for a couple of 'players' and looking at the price of a single guitar, doubling that and expecting a price around that figure (or less), then it will seem very high.
I don't know what a fair price would be and like I said, you can't exactly find another couple of pre-91 Custom 24's with the exact same serial number being sold as a pair to gauge what price to expect - also taking into consideration condition and whether or not they have all the original parts, fully working and any accompanying paperwork.
Anyway, I would like that 10 top Black Cherry - has a great top on it!!