It's this transmission:
https://grassrootsmotorsports.com/forum/201x-classifieds/6-speed-miata-transmission-42k-miles-650/145131/page1/
I used it in my exocet for a single track day, but didn't love the gear spacing on my local tracks (I was shifting it a lot), but my loss is your gain. With the short shifter onboard it's got great feel especially if you're needing a stronger transmission. I installed the short shifter so it's been used for a grand total of ... 300 miles, maybe?
Here it is in action:
https://youtu.be/jYGj3XdczH0
Located near Nashville, TN - I'm not sure you'd want to ship it.
Asking 900 obo.
Willing to trade for exocet OK wheel + tires, miata parts, 255/45r17 tires