Hi Roy. Sounds like a sweet ride and I don't know anybody who doesn't have good things to say about that derailleur.
If by "10 speed chain" you mean 2x5 then yes, any SRAM or KMC chain that is labeled as compatible with 5, 6, 7 speeds will be perfect. 8 speed works as well. Shimano chains are overpriced.
Be careful when buying at a shop. If you ask for a 10 speed chain they will bring you a (very expensive) chain meant for a 10 speed cassette. Ask for a 5 speed chain.