No more aluminum parts?
 

Since when and why gorilla do not make any aluminum parts?

They do, but they only make the chassis for the 3905 emaxx these days ( that uses alloy ), the other chassis are made from CF as its lighter than the stock plastic. They stopped selling the older G3 & G3r chassis for the older emaxx and revo conversions a while ago, since the old emaxx is defunct & the erevo doesnt really need a conversion chassis; it could do with a lower CoG chassis with better battery trays but thats another issue entirely...

And these alloy suspension arms?

Discontinued too ( the G3.3 suspension that I have )- they still sell spares of certain items, but no complete kits. I think you'd have more luck snagging some UE suspension kit ( new or used ) vs a gorillamaxx kit.