Hello Chesh!
Lots of custom content creators are on the forums, I hope some have contacted you.
To help you with your search, indicating your expected cost and rights will help you greatly.
Custom sculptors range from 10L per sculpt to 10k Linden per hour, with a wide variety of skills in each bracket.
As a general Idea, for a pocket watch you might be looking for seven sculpts:
1 Chain Link
1 Watch Casing (back)
1 Watch Lid
3 Watch Hands ( Hour, Second, Minute )
1 Watch Face
Which depending on the content creators proficiency might take 15 - 20 minutes each, for a total of two hours and ten minutes lets say assembled and ready to go.
At minimum wage in my country (Canada) that's about 5400 Lindens, someone in a skilled trade like sculpting or mesh making would fall under might legitimately charge double ( 10.8k) or quadruple ( 21.6k) while someone just starting out might just charge upload fees (70L) or upload fees + tip (570L)
To compare, this is an example of a similar kit purchased in a full permission store: https://marketplace.secondlife.com/p/YEN-Pro-Compass-Watch-Kit-Boxed/3165433
Having items in this price bracket myself (249L) I can say that keeping the rights to the finished product is worth between 1k L ( 4 sales a month ) and 4kL (16 sales a month ) on a conservative estimate. I typically value my items, to myself, on their one month return at 2.5kL or higher (anything less has failed) and assume they will maintain sales for at least six months (15 k Linden bi-annually). Because of this, my sculpts are woth more to me ( 15k ) than I sell you ( 8.64k at 4kL an hour) so for non exclusive items, many sculptors will make them for little or no commission provided they keep cmt resell rights.
Likewise, the more rights they lose, the steeper the loss of potential revenu they lose and the more it will cost to you.
Determining before hand these things will greatly help anyone with offering you a quote:
Permissions to commissioner (copy, modify, transfer)
Rights to original sculptor (resell, resell limited permissions, exclusive)
Scope (This pocket watch is much simpler and therefore cheaper than this pocket watch)
Time Frame (when you expect the product)
Portfolio requirements ( for example previous time pieces )