What I purchased are Stainless steel barbed fittings 1/2 inch ( Brass available too ) I warm the plastic pipe up and slide them in the pipe then I put a hose clamp around them and tighten them while their warm I haven't had any trouble yet but I do watch them carefully for a while .
I am not sure if I can name the place their available on this site so I better not yet but I can E mail it to you if you would like it . They have various sizes available and they have Tee's and "y " s available too .
I do not recomend plastic barbs but they may work . Their mail order and you receive them overnight . They seem to work in other areas I have used them . They are multple barbs on each side .