If you want to try some cheaper priced parts here are a couple you could use:
Nissan part #38323-C6010 is the same as the Toyota Union and is supposed to be cheaper.
You can buy the Toyota Union online from
this Toyota parts seller.
Hardware stores carry a 1/8" NPT part just like the Union that should fit.
A different cheaper tube can be used. I used the fuel line because I know it will hold up to wear and tear.
A smaller cheaper filter can be used. This one was the smallest NAPA had. I saw smaller ones at Autozone for about $1 cheaper. Just be sure it is 3/8".