Want seeds of ugu, fluted pumpkin, Telfaira occidentalis.
I don't have seeds but wanted to suggest that you search under "telfairia occidentalis" (an extra 'i' near the end of the genus name). This has many more hits than your spelling. There are a number of scientific / medical papers about the effects of the leaves, seeds & fruits (summary seems to be: seeds may have some helpful properties for diabetics, seeds are very nutritious, fruit flesh is not recommended for consumption...)
Anyway, with so many people researching it, you should be able to write a letter to them asking about seeds. Or write to the embassy/consulate of some of the countries it's grown in (e.g. Ghana, Nigeria). Some of the pages you will find by searching the right name will give you a list of local names in various countries, then you could write the embassies asking for it in the local names.
Since this is apparently a commercial crop in some African countries, it is likely that there is a commercial trade in seeds for planting. It shouldn't be too difficult to find a source.
Actually the hardest part might be getting it approved for entry into the US...
Telfairia pedata also sounds interesting.