Update: I took a chance and bought the Bulk Reef Supply 20" housing with 3/4" ports. Worked out beautifully. It is nice and black to match all of my other plumbing. It is so strong, I can't imagine it breaking. It has the same tough-as-nails construction as their regular 10" housings. (I know some people mentioned others from different retailers are a little fragile...not this one.)
Here's what I bought:
Bulk Reef Supply: SKU: 200100 20" Reverse Osmosis Canister 3⁄4” Ports $39.99
Home Depot: SKU 811000012753 3/4INX2FT PVC PIPE $1.24 (Schedule 40)
I first tried the boiling water method to enlarge the PVC pipe to fit on the male portion in the RO housing cap. That didn't work too well. I ended up just holding the PVC over the gas stove flame and turning it for about 20-30 seconds to evenly heat it. It slid over the male part on the RO housing like butter. I used my PVC cutters to cut off about 6 inches of the end of the PVC pipe. The hardest and most time consuming part was reheating the PVC and straightening the pipe over the male part on the housing to get the pipe straight in the housing. All in all, about 10 minutes.
I plan to take a little Krylon Fusion gloss black and paint the white PVC pipe to match the housing.
Thanks to everyone for their help and tips. This is a great thread. I will update the performance once I flood my tank in about 3-4 weeks.