DoctorDiff sells custom length axles for $5 more than A-body length axles, so it’s not really much money you’re saving.
And if you have to get custom wheels to get the right backspace to work with the A-body width, you’ll be losing money.
If you’re going to go custom, you might as well pick the width so you can buy the wheels you want off the shelf with whatever backspace they come with. That might save you money, and it might mean being able to use the wheels you really want, vs something that will fit that you don’t hate.