Ooops! – trying to do too many things at once. Sorry.
Correct link …
https://www.ebay.co.uk/sch/i.html?_from=R40&_trksid=m570.l1313&_nkw=6+volt+fuel+pump&_sacat=0&LH_TitleDesc=0&_osacat=0&_odkw=6+volt+fuel+pump
If it is still wrong, just Google “6 Volt fuel pump”. Simples!
There is a non-return valve, not a filter but, if you have any doubts about the cleanliness of the fuel tank, a filter would be advisable.
Your problem does not seem to be vaporisation so I guess your heatshield is doing it’s job.
B…..