The brand of gin I'm looking for?!

If you only want juniper you will need to make your own.

Gin is NOT distilled from juniper berries, it's simply flavored with them. Gin is made from neutral spirit, which is usually made of grain, and then flavored.

I've never heard of any gins that have no other flavoring than juniper.

You might want to try Junipero, which has the most intense juniper flavor I've tasted in a gin, but does contain other flavorings, such as citrus. You could also look for a Dutch jenever. They're kind of known as the original gins, and juniper was the main flavor agent. They can be tough to find in the US, if that's where you're located.

Gin lover, sommelier, alcohol educator

Gin is actually made form juniper berries, it's not flavored with juniper berries.
The berries are mashed and mixed with water, fermented, then boiled (distilled) until one can extract the alcohol (gin).

I would look for a plain Gin - Beefeater, Tanguray(sp), or other premium gins that are not flavored and I think this is what you'll want.

You don't want gin, you want juniper liquor. (if they make such a thing)