The last reply to (or in) this thread was close to two months ago, but maybe I can state here that I seem to remember seeing a National RX-XE520 on eBay. (In fact, a check minutes ago of my records show that, yes, an 'XE520 was listed on eBay as of May 2018. It was offered for $300.00 from Delray Beach, Florida. It came with the caution: "TAPE WORKS SLOW.") Was it this handsome hulk that moderator oldskool69 scored on "the 'Bay"? Can’t definitely say "yep." (You know, I may have found the massive National linking from an eBay listing for an FH-series Sony.) (Shrug)
Alas, my non-repairer limitations daunted me.
And I had already set eyes on another stablemate of the same company (a Panasonic RX-DT75, from Russia with remote).
And, maybe most of all, worry about so big a sound system overwhelming my modest-sized bedroom -- already dealing with two magazine piles, other boomboxes, a big lidded storage tub and several cartons of odds and ends -- kept me from sending the seller payment while enthusing: "Send that National right on here!"