yep - the regular tuttle bases can fit in a deep tuttle box just need longer bolts. Never had any problems, the bolts don't work in bending, as the box takes all the load - unless you hit something that is.
I did have a 51cm deep tuttle made by Select on my old Exocet Speed Slider ( I think it was a 'Lightning'), So you should have no problems sourcing one.
Try
http://www.sunshinecoastsailboards.com.au/fins.htm or
www.caloundracitysailboards.com.au/fins.htmlor any other select stockist
I also had a 46 Slalom Torquay (normal Tuttle) I used with same board - Torquay has stop trading though.
