Regarding #1, you might like this discussion here:
CMP Buyer's guide and other info
Basically, if you can go to one of the CMP stores and examine the barrel, field grade is a fantastic buy. If you are going to have it shipped to you, service grade is probably a better choice.
Regarding #2, No. NRA membership does not qualify. Quickest way to qualify is to go to an Appleseed shoot. Not only does this satisfy the marksmanship requirement, you can join RWVA for $20 and satisfy the membership requirement. See:
Appleseed Project Home
RWVA Membership Only - Eventbrite
... What in particular do you use as a proof document that you attended an Appleseed though?