I don't own a senton so I can't try on and see. But my guess would be no since this body is narrow and a senton is much wider. Sorry bud, but maybe some online forums could help ya out with an exact answer.
You can remove the senton side guards and swap body posts and it will work. The bumpers will look funny though. I completely swapped my senton to a big rock because I kept breaking front bumpers. The big rock is dang near bullet proof. So much so I bought one for my 11 yr old son and getting one for my 3 yr old daughter.
You can only buy the blue body separately cause the blue version was the version1(I believe), assuming you have v3 BRCC. They don't make em in blue completes anymore. Only flat black! However like you! If one wants the blue they simply just buy the body off Arrma's site! Or local hobby shop!!
I ordered a pair of zee batteries on Amazon for my big rock and they both were defective. Had them tested at local shop after one run with them. I just got the replacement pair so hopefully these are ok.