I wouldn't recommend the talking house transmitter since it's audio quality is poor and the frequency seems to wobble with modulation causing annoying heterodyning with any other station on the same frequency.
The sstran seems to get a good thumbs up from most people I know over at part15.us. The ramsey AM1C cost around 30$ but it works on a VFO oscillator so it will drift a bit until warmed up. The AM25 for around 100$ uses a PLL so it won't drift and it's audio is decent.
Very few of these kits modulate at 100% but still will give you good results. With a 10 foot wire antenna and no aerial grounding you can theoretically broadcast up to 1/4 mile under good conditions legally without the need for a license. However you should review the Part 15 rules to make sure you are within specifications. The general rule is 100milliwatts into the last amplifier stage with no longer than a 3 meter (10 foot) antenna, which includes length of ground lead.
Check out part15.us for lots of links and reviews on kits and fully built AM transmitters.
If you have a bit of electronics know how it is also very easy to build your own from scratch.
With a legal full length antenna your whole neighborhood could tune in
