You should be able to use the same spot where the straps were sewn on originally. I have done the repair before and seat belt material works well. I have also used life jacket straps that I found at West Marine. I found that if you put a twist in the straps, you can slip your feet under them much easier. Use Nylon straps, not cotton!

Another trick I did was to install grommets in the tramp where the lacing was attached before. Then, I ran a line through the grommets and never had to worry about replacing the straps. That was a $2.00 fix compared to a $40+ fix getting an upholstery shop to sew the straps back on. I didn't even have to take the tramp off the boat! You can also slip some material like a hose over the line to make it easier on your shins and feet.