Run very fast away from this garbage!!!
The belt is NOT Prussian. It is a Spanish Civil War buckle and it is worth maybe $25 if you could even possibly find anyone remotely interested in buying it.
Whoever the seller is, they have some very "dodgy or sketchy items" they're trying to sell for absurdly high prices to unsuspecting newbie collectors such as yourself. I would stay far away from this unscrupulous person!
Best Wishes,
Alan
225 AUD is like $150 U.S. Dollars. And the buckle and belt is worth maybe as much as only $25. That is very bad indeed.