I used that Thompsons water seal stuff on outdoor timber structure and even concrete ... it's bloody good stuff and the water just beads up and runs off ... but a year later that all stopped.
I dont hold much hope for it on living trees though and pines usually ooze resin anyway. Make sure they're watered well prior to pruning and the resin will do the job.
Here's some really whacky advice, get some eucalyptus oil or aerosol eucalyptus spray and spray the wound as soon as you cut it, that's keep bugs off for maybe 6 weeks.
But paint, waste of time load of rubbish. And from the above info you can see the longivity of any application is lost. Wounds take time to seal over, the smaller the wound the faster it closes, the healthier the tree the better the defences and so on ... best the HO invests in soil conditioning, water and mulch.
Oh, I suppose you cant water them you're in the middle of winter and they're a little dormant in some real cold temperature right?