Capillary tube repair

I am repalcing the refrig unit in my WE-6. I am considering reusing the evap coils that came with the unit, but someone cut the copper lines when the old compressor was thrown out.

I know how to sweat the 5/16" tubing, but do not have experience in the joining cap tubes.

Can it be done?
Is there anything to be cautious about?
Do they make couplers in this small diameter?

Any info is apprecaited '>