Hello mate and welcome to the forum, sorry to say but your buckle is a fake
If figured so, just toss it in the scrap bin?
Try and sell it on ebay as a repro, not sure what they go for but it must have a price!
Cant sell anything with a swastika on it unless it's literature or coins
You can sell it on the classifieds here. Someone will probably pay $10 or so for it as a reproduction. If you don't want to waste the time packing and shipping it, just toss it out.