Looks like a DP 97 to me. If it is its what I use but I warn you , they need a fair bit of work to bring up to scratch ( but then THATS the fun part aint it!!!!!)
The DP 97 was my first helmet.....to shape the dome; using the oven seemed a little dangerous at first so I boiled some water in a really big pot..it Worked great...took a little longer but I was able to heat up the dome only and not the whole helmet....
The DP 97 though is really fexible when heated, so becareful and don't leave it in a hot car..FYI.