Heads up, Dave!
There must be at least dozen of students/hobbyists fitting your requirements living nearby, what you are asking for is not unreasonable at all.
You might even consider adding requirement for basics of programmable logic design, if you are seeking for someone in the higher end (read: not lazy to learn).
Such people do exist, only thing is to make it interesting enough for them - sure, publicity and valuable point on resume is something, but what range of project can one expect to work on as lab assistant? You are quite vague in the definiton. Such people, if bright enough, will be sooner or later noticed by someone from industry and be sure they will happily take any field related job when offered. Once bit more expirienced, they will be more and more picky and tend to choose only work related to topics that interests them - so offer something exciting to tinker with, not only vague "what suits your capabilities", then it's on to you to evaulate candidates if they are capable enough to fullfill project goals.
I'd always go for something that interests me even if it's paing less in multiples of what I can earn with my skillset - just because then I can fully enjoy my work and in the end it was all fun. As bonus there are new skills gained with minimum effort required. Another factor I value much more than money is work collective - working with enthusiastic people having same taste of humor as me is priceless, bonus points if it is small garrage company and we are all acting almost like a big family.
BTW: one mistake I see repeated over and over around me - Why do people expect to be taught anything by a school?
Teaching or learning something solely based on memorising facts instead of fully understanding them and applying them and hence encouraging student to be interested in more details is utter nonsense, but not uncommon at all - schoolar system can be fairly regarded as broken in this way.
Also, students will choose path of least resistance in most cases - why would one bother to understand, when memorising random facts is enough to pass exams? And this applies all the way from elementary school up to the college. I'd bet you will choose someone who's fully, or almost fully selftaught, (just) because it's this way nowdays.
Before one starts flamewar based on my post - I'm not trying to sound like elitist dickhead at all, I'm just summing up all my up to date expirience and my viewpoint leading from it.
To be more detailed on my backround: I'm in my early 20's, working for small company focused on highend chemical instrumentation, doing all suff related to hardware, including low level firmware, HW design (from concept trough prototypes, verification, PCB layout, HDL design all the way up to manufacturing preparation and material sourcing), almost all of the mechanical related stuff (or least doing documentation for third party companies). Other guys do rest of the firmware and software work, bureocracy, chemical research and so on. Previously worked about two years for another small company focused on LED technologies - some of it was medical, some aftermarket automotive. I've got my first serious paid project back when I was 16yo teenage.
And you know what ? I'm selftaught. I know about at least three other people in my age brighter than me in our region (and that's about 200k of people in total and fairly limited by my social awkardness), all of them selftaught, too. Such people exist. Just keep looking and make it interesting for them (I'd apply in a heartbeat, BTW - if only just not living on the opposite side of the Earth
).