A solution that I have found works for me is to make extender handles onto the *syringe with Thermo-Loc. Thermo-Loc is a plastic material that softens in hot water, becomes malleable, then hardens as it cools.
I also use it for setting stud/post earrings and cufflinks, and holding items when engraving. I bought mine from Sutton Tools, after they gave me a free sample at IJL one year. You get 15 sticks in a pack, and as it is reusable - it should last for ages. Very useful stuff!
*If you use metal clay in a syringe it should work for that too!
|Sticks of Thermo-Loc|
|Crude but practical - extender handles for paste solder...|
|... makes it much easier to use once you get towards the end of the paste!|