I've got this one:
https://www.amazon.com/gp/product/B00N3PPZZY/ref=oh_aui_search_detailpage?ie=UTF8&psc=1
Supposed to be the same as the Pyle and others.
I've got an extra oil cap so I just need to get it together and I'll make a DIY and I can send it around for folks to use, although the shipping to/from would come to a significant % of the cost of the whole unit itself...