Quoted from the FCC regulations
§ 95.218 (R/C Rule 18) What are the penalties for violating these rules?
(a) If the FCC finds that you have willfully or repeatedly violated the Communications Act or the FCC Rules, you may have to pay as much as $10,000 for each violation, up to a total of $75,000. (See Section 503(b) of the Communications Act.)
(b) If the FCC finds that you have violated any section of the Communications Act or the FCC Rules, you may be ordered to stop whatever action caused the violation. (See section 312(b) of the Communications Act.)
(c) If a federal court finds that you have willfully and knowingly violated any FCC Rule, you may be fined up to $500 for each day you committed the violation. (See section 502 of the Communications Act.)
(d) If a Federal court finds that you have willfully and knowingly violated any provision of the Communications Act, you may be fined up to $10,000, or you may be imprisoned for one year, or both. (See section 501 of the Communications Act.)
Now you can see just how expensive the fines can be...
Unfortunately, I can't make suggestions for which radio to use for your truck. I only fly RC planes, and our radios are somewhat different. The laws are the same though.
I would suggest you ask for suggestions in the
RC Car Radio Equipment forum. Keep in mind, many RC car enthusiasts either don't know or don't care about the FCC laws I have mentioned. Some will tell you it is OK to change the crystals in the transmitter, but just remember the fines mentioned in my quote...
In the end, it's your choice. I just want to help prevent you from breaking the law and facing stiff fines or jail time (95.218d).