hifi engine

Noob question about AKAI 635D

Hi everybody,

I'm new to this site, I hope I follow proper etiquette.

On the photo this device has 10" reels adapters. I'm looking for these adapters. Where I can find them? Are they "AKAI" ? Or it is something custom?

I found a guy on eBAY who sells "special edition" adapters (approx 50$) and some aluminum adapter's hub ( 163$, but they look pretty cool indeed). Just search eBay by "FX-301 REVOX A77 B77 PR99 ALU NAB ADAPTERs HUB" - you'll see plenty of them.

My questions are:

1) 50$ for plastic adapters - is it fair price? Is there a place to get them cheaper?

2) These aluminum hubs - besides aesthetics - do they improve anything?
Will they work with Akai 635d?

3) The adapters on the picture - are they "AKAI" ? Or it is also something custom?

If I'm asking in a wrong place - could you advise proper forum?
Thank you very much.