If you love Sun keyboards AND want a compact keyboard, try and find a Sun Voyager keyboard. It's a Sun keyboard, but without the (pointless) numeric keypad on the right. When I worked at Sun I managed to source a couple and still have one in my "I might need that again" bin of parts.

I didn't find any on ebay, but I did find a whole Sun Voyager system https://www.ebay.com/itm/WORKING-Rare-SUN-Voyager-SPARCstati... $700 just to get a keyboard is kinda pricy.

Like the author of the article, I like the Happy Hacker keyboard. It's compact, well built, the control key is in the correct place, has well placed arrow keys, and isn't overly expensive. I have (I hope) a lifetime supply of them. So long as I can get ps2 adaptors for whatever comes after USB.