Perhaps have the vendors you use do the legwork for you. That's an added benefit they can provide you, as a buyer. I have a vendor that does just that...I can order parts online, see availability, and even check labor guides, interchanges, and fitment. Because of that, it's my first place to shop. Really where I get nearly everything, because it is consistent, and they have shown they take us seriously by providing us with tools to help the ordering process. If I know part prices, associated labor, etc., it means many times I can make a decision on the fly. We are a mom and pop and do straighforward stuff with some classics thrown in (and the occasional tractor dropped off in the lot). It also helps in a small shop, if your front-end person is not necessarily a car guy (me). By providing that info to the desk person, the wrench doesn't have to stop and weigh in on an estimate (increasing bottom line). Just a thought...the information must be out there...ask and you just might receive, if they can see how it would cement a relationship with you!
Cheers