Watching the youtube video linked on this forum shows the vacuum infusion being done with the following so that the spiral delivery tube fits in the slots in the connector. I haven’t found this in the States. What are you guys using? Thanks! 
I bought a few rubber stoppers^^^ at Lowes, drilled/cut them similar to those in your picture and use those. Cost about $2-3 a piece and work great for my needs.
Airtech makes a similar looking product called a RIC (resin infusion connector) and should be available from any airtech distributor.
The RICs are handy and reusable but t-fittings are not that hard to use and are cheap and readily available.
Also, If I can prevent it, I do not make holes in the middle of a bag. Even when you want a feed line in the middle, you can get resin to it by adding a tube below the bag, in a pleat.