engineered wood flooring nailer
I ran into the same problem except my flooring is custom milled 3/8" thick x 1 3/4" wide oak to match the original flooring in my 110 year old house.
I looked at a myriad of different options. I called the only local tool rental place in town. They only rent pneumatic & non-neumatic nailers for 3/4", not an option. I asked a few guys that I know in the trades and some told me that in the past they just used an 18ga brad nailer and free-handed it. That was a non-starter due to the fact that I didn't want any problems with blowouts and improperly shot brads plus it would take a LONG time to do it without guaranteed good results. I spent a good chunk of money on the flooring and didn't want to make any costly mistakes.
So, I looked some more and found that Porta-Nailer sells a pneumatic nailer that has a specially designed shoe that holds the nailer at a precise angle to shoot 18ga staples directly through the tounge. At first look I thought it was pretty pricey. After weighing the pro's and con's, I bought Porta-Nailer 461 for a little over $200.
As far as the flooring project went, it was the best $200 I have ever spent on a job specific tool!
Here's a picture of the nailer, good luck on your install whatever route you take!
After I got the pressure dialed in and tested it out on a few scrap peices I was satisfied and ready to move onto the big project. The nailer performed flawlessly. I had zero problems with it! All the staples drove properly with 0% requiring any extra help to set them to the proper depth.
On a side note, the flooring adapater is removable so the gun can be used as a regular 18ga stapler.