Old pocket watch valuation

If you pop up a couple of pics here that might help. Pics of the movements(if possible) would really help as pocketwatches came in different grades and quality. Though in general vintage pocketwatches are not nearly as collectable as vintage wristwatches, there are some that are, especially among American collectors of American made pocketwatches like your Elgins

As for value, real world value, one of the better places and free is none other than ebay(though it's declined of late). Look for similar examples of your Elgin and see what prices they actually tend to fetch. Look on ebay.com rather than ebay.ie. That way you get more US buyers/sellers.

Rosahane's is a good shout for auction houses, though I have found(especially here in Ireland) they tend to either overvalue or undervalue watches. Expertise can be, and I'm being kind here, variable to say the least. Jewellers tend to be even worse, unless it's a current or newer model of watch. Antique dealers ditto.