Trailer parts

[tamiya fan]

You can use part #s (more than one) and search for it online. If you have the part #s try at Tamiya USA. Some times they are out of stock on items, sometimes not.
The place I like to shop for what you are looking for is Semi Joes Truck Shop on Ebay. He will usually have the suspension in a FULL set or two to complete what you need. If not, searching ebay will bring some items up also. Part #s for the search is better results.

Try Semi Joe first! Great place for what you are doing.
Sorry so long but giving you the best options. Hope this helps you! Good luck with your build.