After market heater??

I just resently bought a 74 beetle and it has no working heater...i'm up in canada so a strong heater is a must...it had a gas heater in it but it was disconnected, now i've heard bad things about those gas ones so i kinda sant to stay away from it and install an electric one...doesn't anybody know of any aftermarket ones u can get? or if i were to rig one up myself, how much power is too much....

I dont know much about the heating system of my car (1972) and I am not sure if its similar to yours or not, but are you sure you dont have to just reconnect the heating lines? I have always been under the impressionn that the heating system was rather primitive....hmm.
A friend of mine disconnected his to work on something and forgot to reconnect - went 2 years with no heat because he just figured he needed a new one.