There are problems with Heathkit-type kits in todays electronics world.
First, electronics has gone to surface mount, and you cannot realistically sell kits to beginners with surface mount parts. The whole point of Heathkit is that beginners could learn electronics by building their kits.
Secondly, modern circuits with micros, fpga's, and other LSI chips are much harder for the average person to debug then the circuits of the 60's.
Third, back in the 60's, the profit margin of electronics manufacturers was so high that Heathkit could sell kits that were cheaper then the equivalent manufactured products. Today, manufacturing is so efficient that selling a kit can often be double or more the cost of manufacturing a completed item. If you want a large screen TV, do you want to pay $600 and get a TV that will probably work perfectly for 5 or more years, or do you want to pay $1800 for a kit that has a high chance of not working, probably will not be reliable and will probably be an out-of-date design?
There are still people selling kits, but you will not find much with the class of Heathkit.
You can find kits, like this one from Australia:
http://www.altronics.com.au/p/k3218-dual-tracking-0-19v-power-supply-kit/but it is a 1980's type of supply in a creaky unshielded plastic case. Could easily be 240V only, but you would have to check the Silicon Chip magazine article the kit is based on to find out. You probably want to do better.