the rear wheels are the same as 2wd rears so proline and losi will both fit. Tamiya and yokomo wheels off the 501x and the bx will also fit but these will require an adapter as i believe they use a hex drive not the pin
for the front you can use losi i have seen these fitted to the d4.
tamiya 501x and yokomo bx both have the same sized drive hex but i think the hex is deeper so this might catch on the hub without trying on a cay i can't confirm.
At the moment proline don't offer a 4wd front wheel but as there is an almost standard sizing this might change as only kyosho and ttech currently use different wheel fittings
for tires just use the versions marked 4wd front by losi or proline. The other option is to cut'n'shut the rears to fit if this is allowed for the races you participate in.