1. Single flanged bearings : A hand, a minidrill with cutter, a file, some minutes
Stick the bearing on an axle, so you can hold it easier, cut off the major excess with the minidrill and do the fine work with the file.
Or - what I did before I got my lathe - I glued the bearings on an axle with superglue and removed one flange in the minidrill with a file.
A bit heat afterwards removes the bearings from the axle, soak them in acetone, take an acetone - wet pipe cleaner to get the remains out - ready.
I always made some more than actually needed - who knows....
Sorry, I'm a scratchbuilder. The time to waste for searching is often not less than making various things oneself. But less satisfying.
2. Tyres :
http://slotcarparts.de/index.php?cPath=24_25Carsten also makes tyres on demand for a reasonable price. And shipping from Germany to the US is much cheaper than vice versa.
Roland