.....so, first of all a class A amplifier would dissipate aproximately
1W which isn't so bad. any TO-5 transistor with a clip on heatsink will
take that. A 2N5109 would be ideal, being a quite rugged device. you
don't have to worry.
second, about 12-13 dB of gain in the HF range would be an approximate
maiximum for easy and comfortable construction. higher gains are
possible, but you start to endanger yourself with oscillations. better
a 2 stage amplifier, even though it sounds more expensive. it's only
one of a kind so cost shouldn't be a main concern.