Here are those seals I was telling you about. I will interchange your part numbers at work tomorrow, but I am pretty sure these seals would work. These cost me about $2 each. They don't look like a bad seal, but if you wanted a better quality one, like a BCA/National, it would probably be around $11 or $12 each. I plan on using these in my second ST/300/D.
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-Attex ST/300/D - "The Duck." Family owned since the early '70's
-Attex ST/300/D- Resto/mod project! (not yet started)
-Attex 440 Thunderchief Racer (not yet started)
-Attex ST/400 (not yet started)
-Hustler 980 BIGFOOT- A work in progress (SOLD)
-1999 Max Buffalo Truck (SOLD)
-1989 Max IV - A Max four my kids. (In progress)