Hi Doc, welcome. Yes a very rare bike indeed. I don't have mine anymore but mine had a Villiers 200 piston in it, & the carbs are a Villiers part, so some Villiers parts are interchangeable. You may find some Villiers parts on ebay UK & even ebay USA, sometimes whole motors are on there. I think a Villiers 2oo motor would be interchangeable. The motors look different on the outside (squarer motor cases on the Enfield mini bullet) but Enfield India apparently copied the Villiers, that's why the Villiers piston fitted into mine.
I hope that helps.
I liked mine in it's cafe racer format, but I believe the next owner turned it back to stock.