Oak Hills Research QRP Explorer II, 40 Meter QRP CW Transceiver.
$50 at local hamfest, with power supply.
Fits in Milsurp British gas mask bag, re-purposed as radio bag. Just add simple dipole antenna, CW key, headphones, and SLA battery/charger for field use. Probably get on HF for around $100 total.
Some of us were fortunate enough to have a decent job and an amount of disposable income that enabled us some leeway when putting together our comms kit. Many of you out there are not, and this post is for you.
The important thing however, is not what model of radio you get for your comms, but just that you get something that works and you get on the air with it.
If you and your buddies are willing to learn CW and try QRP (low power) HF amateur radio, then you can get on the air for not much more than what your squad radio cost you. With simple antennas you can all get on the air and help each other learn CW. There is plenty of spectrum on the 40 and 80 meter former-Novice CW sub-bands where you can practice and no one will bother you. Actually, some OT may notice all of you trying CW and help you out. CW ops are like that. Especially the ones who hang out in the old novice sub-bands.
You can even learn CW by yourself. http://www.arrl.org/code-transmissions
The ARRL has MP3 files on that page for those of you without an adequate receiver, but even if you have something like a Tecsun PL-660 or similar shortwave portable that does SSB/CW you’ll be able to pick up the ARRL’s CW practice broadcasts. Getting it off the air is good practice, especially when trying different antennas to improve reception.
Looking for a cheap transceiver? Go visit your local hamfest or try an Ebay search on QRP Transceiver. There’s an OHR 40M QRP rig on there right now for $50. Also a lot of kits that use discrete thru-hole components that look like a pretty easy build. Some are even under $20. They will get you on the air, and you can fix them if they break.
You and your buddies can buy them, build them, get on the air and practice.
And that’s what’s important.