i do not know what is a sonic tape. i remember that there were 'cloth' tape which coiled round and for measuring medium distance(more than 10 metres) in (more specialised) hardware shops.
Erm... I'm not very sure abt it. But u can prolly get those like a wheel? The one that has like a ticker built in and a wheel where u roll the wheel on the floor and den look at the ticker for the actual distance?
Cheaper somemore, less maintainence compared to those fancy gadgets.