Roxanne applique needles and John James Milners are my favorites, size 10-11 usually. I also use silk thread for hand applique ( and most of my hand sewing)
See if I can explain this so it makes sense without pictures-- to keep your silk thread from sliding out of the eye of the needle while stitching-- thread needle, pull thread through about 2"-3", hold long end against back of needle, take end that you threaded through, and thread it back through creating a loop, tip the needle through the loop and pull the two thread ends tight. Both ends of the thread will be on the same side of the eye- locked in place, one a couple inches long the other as long as you cut your thread. The thread is ( locked) around the needle- will not slide out. ( when ready to change / rethread needle just slide your nail down the eye, shaft of needle to open the loop again) this works with any thread - I was taught to thread my needles like this year's ago by an elderly lady who hand quilted.