Trajan Silver "SpQR Optimo Principi" - Help

with your reservations, but I will still go with my first inclination when I first saw it:
"Yeah, it's a good coin".

"Poor effort by the celeator," was another of my thoughts.
Style otherwise OK.
Those minor flan splits are pretty hard to imitate like that with a modern production.

If you google "trajan silver denarius) you will find all sorts of prices. You won't get a dealers price, but check out past sales on ebay, look for one in similar condition as yours with a similar reverse.

The seller is asking for it 230 US dollars and says it's worth around 700. Is it true?

For 'suckers only' it should read. No the coin is not worth anything near that price. I have bought a Trajan denarius in the not to distant past for $25 in a slightly worse condition. The victory reverse is not rare for a 'Generalissimo' Emperor who fought more than his fair share of wars. In this shape I could see a dealer asking anywhere between $50 and $150 (the former if he wanted to sell it the later if he liked the way it looked in his case). This is a nice coin but if you are a patient buyer you might find one just as nice for under $75.