New or used cartridge

@terry9 
They're just a deputy service that facilitates the transfer of Japanese goods. They would route your cartridge directly to Koetsu Japan (which is the only place to receive a genuine rebuild) on your behalf, just as if you were a Koetsu owner living in Japan. I haven't yet used EIFL myself, but it looks like a viable option, and I've used deputy services from Japan in the past for purchasing other goods (often of quite significant value).

@handymann
Yeah, trade-in won’t get you much unless you can use it as a bargaining chip for a dealer that’s willing to cut into his margin. Probably better off selling the Urushi yourself.

The stone Koetsus are all wonderful, though unfortunately I haven’t heard an Urushi. The differences between Onyx, Jade, and Coralstone are all relatively subtle. They each have better (more powerful and clean) bass response than the RSP. The Onyx is a pretty excellent all-rounder. The Coralstone is a slight bit more warm, organic, and fleshy sounding. It is probably the best sounding, overall, by a small amount. But they’re all great and give the full dose of Koetsu magic. Don’t stress too much over the stone differences. I highly recommend any of them!

Do give consideration to the amplification needs of a 0.3mV output platinum. The Bob's Devices Sky SUT's make for an extremely synergistic pairing with any stone Koetsus, for a very reasonable price.

My KRSP with diamond cantilever has a subtle but unique smoothness in the mid to high frequencies. I attribute this to the fact that the stylus and the cantilever are one piece of diamond - but that's what I was expecting, so maybe I'm fooling myself. Worth $4000? Don't know. But I'd like to compare it to a stone body on my air-bearings.

@mulveling 

I've also heard that Koetsu will not touch a cartridge that's been worked on by any 3rd party.

Not only Koetsu, but almost every respected manufacturer will not touch the cartridge if it was refurbished by somebody else before. 

About SUT’s - why not DIY? You can get raw transformers from Lundahl from K&K Audio that are out of the park. I use a pair of silver 1931Ag; less than $2k. Cartridges wear out - SUT's, not so much.