It appears that the Garrett Infinium LS has been permanently dropped from the US lineup after a long spell on the market.
There's no doubt it was getting pretty long in the tooth, and never seeed to be accepted here as a popular gold PI, nor was it very sensitive to small gold when compared to the current offerings. Admittedly mine was mainly used for beach hunting, of which it punched pretty deep, particularly with the mono coils. The S-bend shaft was a bugger to carry around for long periods, with many including myself opting for a straight shaft configuration.
It never was the most user friendly PI detector out there, and was a pretty high maintenance machine to own. My infinium was an early unit requiring the main board to be upgraded to enble it to run mono coils and also ground balance more successfully on mineralised ground. The large DD coil with the thinner gauge wiring died early on, cable strains and earthing issues were commonplace, the fiddly waterproof connectors were also prone to bent/broken pins.
Garrett should probably look at producing an ATX in conventional detector setup, preferably with a straight shaft and hip/chest mounting capability to reduce the weight of the current military style configuration. The overall cost of the ATX, especially with regards to the hefty coil prices also needs to be addressed if wanting to have it accepted as a more viable option. Especially the case considering the Infinium coils were nearly a thrid of the price of the current ATX coils - $939 for an 8" ATX mono is pretty insane pricing for a small coil.
Garrett Australia are still selling the Infinium, presumedly to clear current stock. The very similar Sea Hunter MK2 is still being retained in the Garrett lineup both here and in the US.
Here is a link to the Garrett International range of products, with PDF links or full zip file of the catalogue on the right of the page:
http://www.garrett.com/hobbysite/hbby_catalog_international_en.aspx