Ok first of all you are not alone... You are in luck that most custom knives are made very well...however finding them is a royal pain in the ass and most places are subpar and usually out of stock. The best website I found was
http://www.threelittleindianscustomknives.com/ they have just about every major knifemaker out there in your price range.
As for knife makers a lot of the famous "old Dogs" do not take orders any longer and if you find one can cost thousands...However in my humble experience I found talking to a really good knife store owner like Lawrence Amoroso can help you as he helped me because I had a lot of questions about flippers...you like thumb studs so you have different parameters as I do. There are 3 types of knives...production which are mass produced and have many compromises, mid tech knives that have common parts sharing and things subcontracted like knife grinds or scales, heat treating or hardware like screws and finally full custom knives that are made by 1 guy. Full custom and mid tech have the best quality but a mid tech knife won't have the same fit and finish as a full custom.
My favorite knifemaker is Randy Deucette
http://web.mac.com/lacigars/Three_Little_Indians_Custom_Knives/Randy_Doucette.html
Randy is in Canada so the dollar favors us in the USA and he is relatively humble and has been making knives about 10 years and uses higher quality S30V where other guys use a cheaper CPM154. He is not an old dog and you pay more for product than you do "name" for his full custom folders that are around 550-750 bucks. Randy also likes people and will talk to you on the phone and he still takes orders and can get you your dream knife the way you want in a few months instead of a year PLUS like other custom makers if you can't find anything. I got this knife today and it is perfect for me with a 3 3/4 inch blade and a smooth flipper that kicks ass.
http://web.mac.com/lacigars/Three_Little_Indians_Custom_Knives/Randy_Doucette.html#44
So I would call Lawrence at 917-577-1472 tell him DHaines sent you
I do not endorse this site or anything and other makers to ask about and look for are
RJ Martin
Les Vorhees
David Mosier
Hope this was helpfull any questions feel free to e-mail me back.