Recommend me used 26" forks for Whyte 19

As the title says: I've just bought a used Whyte 19 frame to build up as a project. Initially at least it'll be used on some easy forest tracks in Dalby Forest and generally non-technical tracks on the North York Moors. I need to buy some used forks and being a newbie to mountain biking I haven't got much of a clue. What should I be looking for (features, brands etc) if my priorities are: 1. Quality of ride, 2. Durability, 3. Likelihood of finding a good one on ebay or similar and 4. Price (in that order). Many thanks