Easiest to get +.100" 3/8 stem Manley 2.19 intake valves. Stock length exhaust valve.. The exhaust side will need a rotator eliminater. I use a large 5/8" ID - thick, flat washer ( TSC gold color) and a .060" spring seat. This will give you a correct spring height to build from.
Correct way to do 2.19/1.88" Is with a Serdi type cutter. This will blend the correct angles into the chamber. A 70+ degree "Bowl Hog" will open up the bowl below the seat.
Cut heads .020". Use a short dome (.200-.250") piston Probe has an inexpensive set that works great.
Check the prices. I love to do these but, in this area the total cost, including cores, is more than a set of new aftermkt aluminum oval ports. (Ebay around $750-$800.00)