Man, I need to check in more than every couple days, this is a pretty fast moving thread.
Wipe needle with alcohol, light it with lighter until red, wait a sec, wipe with alcohol, insert into jar, release spores, pull needle out with micropore (side question, would durapore tape work?) tape ready to cover the hole in the tyvek.
I think I can help you out a little with your methodology. While I have absolutely no mushroom growing experience, I do have a bit when it comes to handling biological and toxological agents. You should not bother using alcohol. Alcohol works well to kill bacteria and prevent staph in hospitals but it will not reliably kill virus or spores. Heating the syringe over a flame is adequate but if you wipe it again with alcohol, some of whatever you wiped off the first time gets wiped right back on except bacteria. When it comes to micro organisms, "some" is the same as "a lot".
Now for sanitizing surfaces around your "lab"(not to be confused with sterilizing) I suggest the secret chemical that labs and NBC crews worldwide use for cleaning up bio-weapons.
Sodium hypochlorite in an aqueous solution, aka household bleach (check the ingredients for sodium hypochlorite to be sure). For these purposes mix two parts water and one part bleach, that simple. The stuff is extremely anti-life.
The only plastic I know of syringes being made of is polypropylene. You can chuck those in an autoclave no problem and those things nearly go to 300°F. As long as you're not going over 300° you'll be fine. If you feel like getting "sciency" you can google around for a triple point graph of water or find the equation to convert 15psi to the temperature but I'm pretty sure you're safe to PC them anyway.
Only thing that should be different is since there is no way to dry and pacakge your syringe (those tools at the dentist are not new, they get sterilized and packed on site) you'll have to just fire up the PC and not open it until you're ready to work.
Shit I typed more than I planned, but I didn't have time to type less so bye now.