Hi there,
For your caps see if you can get NP0 ceramics, NP0 do not change much with temperature, for your trimmer caps you might well have to use plastic die-electric ones.
I have just been working on an fm transmitter for testing and listening to my old time valve radios, I have used 2n3904's and bc547's, they both work well.
You should be able to use a radial cap instead of an axial one, just bend the leads to make it axial (it might be done for a stability reason keeping the 2 connections apart).
The 10pf accros the collector emiiter on the osc transistor wants to be very close to the tranny, if you can solder it to the legs of the device on the top side of the board.
If you want a really good circuit that is very stable frequency wise have a look at this one, I just built it and it works well.
Crystal Locked FM Bug
Edit: word of warning with the trannys, the 2n3904's have the same pinout as the pn2222's on the schematic, bc547's on the other hand have a diffo pinout, you need to solder them in 180 degrees rotated (the end 2 pins are reversed).