I was lucky to find some nice aluminum mount spin on fuel filters so I bought some for future projects with spin on filter included. I have some extras for sale for $40 each plus $10 shipping, or buy two filters for $75 and shipping is just $15. Several different easily found replacement spin on filter elements fit it, like a Fram P6503, or Wix 33195. 1/4" NP with 1/4" tube adapter fittings. Here's some pics of it with dimensions.