Old Pen Pad with Apple serial bus

Hey, I have an old apple penpad that uses an apple serial bus to connect to the computer and I have grown out of the serial connector. I need a cheap way to connect to the computer with the serial bus. I don't want to spend over $50 US on this project. My question is whether to try salvaging this Penpad with an adapter or just buying a new one.

Have a look at this and see if that will fill the bill. Who knows you might then be able to locate a second hand unit?

USB to RS232 Serial Convertor -- DataPro

Thanks for the link but for $10 more i can get a pretty nice new one. I think that is what it is going to come down to eventually.