First the 312 is a great looking piece. Cost would be around $7,000. It is a contemporary model
For most collectors like myself and let me qualify this by saying I have 11 Panerai's, the historic look is prefered by most, but not all. The 000 costs around $3800 and the 005 around $4200. If you are starting out this price level alows you some leeway to Put Away the original strap and buy 1 or 2 others with the money you save.
Final result you enjoy the first Panerai and you get to go crazy with trying fiqure out a strap. Their are so many that you will learn quickly.
Just my two cents!