I've always been puzzled at the military resistance to everyone being basic small arms qualified. Spend millions of dollars on one freaking missle and yet scream about money when it comes to teaching our troops at the pointy end of the spear. OK OK so you are on a boat. Does anyone remember one of our boats being taken by the North Koreans....?
Is there any guarantee that you won't be tasked with shooting your way out of a bad deal? Oh yeh, I forgot - spend five years in a POW camp as the alternative.
If you have the money to spend for some basic small arms instruction, consider it an investment in your future and ability to defend yourself and your turf and family. In todays environment it seems like warriors and their ability to defend whatever in hell they signed on for is handicapped by "Oh My God - he is using a real live gun..."
I began my small arms instruction when I was five years old by my father who was, of course, Marine Corps. It continued for the next 65 years and I'm still ranked in the top 10% of pistol shooters in the entire freakin world. So you might ask, what have you done lately? Well, I have trained my wife to be deadly with pistol and shotgun. When my son gets older I'll train him the same way. Neither of them will have to ask for someone else to do it for them when the SHTF.
I applaud you for even thinking of qualification with small arms. $150 is not a huge price to pay for that instruction and consider it a down payment for more training. If the Navy won't pay for it and you have the money, go for it. Even if you have to cut down on costs of a few 6 packs it will eventually allow you to decide if you want a 6 pack or a case.
You can't begin to imagine how much respect you'll get if you can show some expertise with small arms regardless of service. But in particular, the Navy with its attitude about using a missle or a big boat when some clown has an AK pointed in your face up close and personal. Think it can't happen? Doesn't take too much of a google search to find numerous incidents. Been there and done that.
Go for it.
Semper Fi
Rocky - Distinguished Pistol Shot, Presidents 100 and grad of several civilian schools of gunfighting.