There's no need to replace sensors if they were working ok, rather than putting in some unknown ones, even knew ones can be duff, if the belt and tensioner are ok they also don't need renewing, as for gaskets I use cometic so the only one I'm buying is the HG at about £50.
I'm keeping all the costs as I buy/get stuff done, incidentally mine is still on std size bearings, but they was something "odd" about the thrust clearance as it was massive.
tabetha