#1 is a Dynamic chassis with Dynamic rear wheels. Any threaded wheels will work. There are a number of modern guide flags that will work. Paul Gage makes tires for darn near anything so you should be OK.
#2 is the Strom GT, and I don't think you can get those long bladed guide flags anymore. You can try some vintage suppliers but your best bet is probably putting in a pin or converting to using a modern guide flag.
#3 is a Revell ladder chassis with an old Mabuchi motor and what looks to be no motor mount brackets (probably why the motor won't stay in the chassis).
#4 is the original Strom chassis that goes with the Jaguar body in picture #3. Press on rear wheels on splined axles so new rears means new axles first unless you get new Strom wheels off eBay.
EDIT: There is a batch on the auction site now:
http://www.ebay.com/itm/Vintage-1960s-S ... 5b04cc237e