Here at GDS we have compiled a quick reference guide showing the sizing of the Canon TM-300 and TM-305 printer. The Canon TM-300 and TM-305 have the same dimensions. The only difference between these two printers are that the TM-305 has a 500GB Hard Drive plus you can print direct from a USB drive, which the TM-300 does not.
Hopefully this will help if you are thinking of buying a new printer and want to know if you have the required room to house it and to install it in place initially.
Canon PRO-4000 dimensions