Rusted supports on Eagle trialer.

I have an 18 year old Eagle trailer and the plates that hold the bunks have rusted almost completely. I am considering getting new plates welded to the top of the support beams but I am wondering if anyone knows anything else that could maybe bolt to the top of a beam and support bunks? I am also wondering if I should buy a new trailer? Is an 18 year old trailer too old? I don't see major rust anywhere else.

Just google trailer bunk brackets and you will see all kinds of bolt-on options. I'm partial to eTrailer.com because of their service and support. Having movable brackets allow you to adjust the bunks just to where you need them.