I use these: https://www.ebay.com/itm/362777100729 They are cheap, they work, and they are available in several colors. One thing i did learn, Loc-Tite the nut that holds them on or it will come loose.
What about these: https://www.ebay.com/itm/4pc-RC-1-8-Paddles-Buggy-Tires-Hex-17mm-Wheels-for-Snow-Sand-Master-Off-Road-Car/143756135648?hash=item2178888ce0:g:tQwAAOSw~gxfbpBg They are a bit large though, at 4.9" outside diameter. The stock Arrma DBoots are a 4.1" outer diameter, which should be...