What are the actual dimensions of the batteries? And where could some one buy said batteries?

Last year they were NP18-12 batteries. From the data sheet:

Dimensions (mm)
Length 180
Width 76
Height overall 167
Weight (Kg) 6.2

They are available from various suppliers.

However, I would not go buy any thinking they are going to be competition legal until kickoff, as there is always the possiblity it could change.

Thank you but I was actualy looking at using one for a different project.

In that case, they or an equivalent are available from most battery suppliers. I usually get mine at Batteries Plus. You can mail order them, but the shipping on a 13 lb piece of hazardous material is kind of painful.

The dimensions are pretty standard for a 17/18 Ahr sealed AGM or GelCell battery.