Some woodworkers supply stores sell a device for injecting glue that is
close to a syringe that may do the job for you. They are entirely made of
low quality polethylene and have a poly "needle." Not high quality but they
may work. I have seen in some woodworkers stores a medical syringe modified
so that the standard needles cannot possibly fit. These are probably your
best bet if you can find them.
Anyway try the woodworkers stores and big hardware stores if you live in an
area of low cow, pig, or horse population density.
Gene Robkin