As someone posted, the closest thing you can find to live pto is the Yanmar powershift. With this transmission, you can put the tractor in one of multiple transmission ranges, powershift in neutral, engage the pto, and release the clutch. The pto turns, the tractor doesn't move. Now shift into one of 3 forward gears or reverse on the powershift and the tractor moves.
In general, putting belly mowers on these tractors can be a challenge. The options are to run it from an electric clutch on the front of the tractor, or from the rear pto. In both cases, belts and pulleys transfer the power to the mower. Keep in mind that the front pto is "independent" due to the electric clutch. The rear pto would not be "live/independent". The major problem is that these tractors are of an "axle back" design. The front axles are placed further toward the rear than most US compact tractors. This causes problems with fitting a reasonable size mower between the front and rear wheels.
I have mounted a YMM45 on my YM1301D. I got the deck complete with the electric clutch. It was designed to go on a YM135/YM155/YM155D. I could mount a larger deck, but for my purposes this is sufficient. If this is to be your tractor, and you wish to keep it indefinately, then go for it. Find a Woods 348 or whatever and give it a shot. With some fabrication and machining, you could make it work. I have even relocated the front axle on a YM1110D to accomodate a belly mower.
Greg