All OTC stocks can be shorted. You just need to find a broker that offers this service, and then the broker needs to borrow shares and make them available to shorters. Interactive Brokers is one of the largest, most reputable brokers in the world, and allows shorting of OTC stocks when borrows are available.
Finding shares to short is always a challenge.
The "real" short position data is published by FINRA bi-monthly. Once the mid-may short position data is published, you can go to OTCmarkets.com, enter the ticker TALK, and see the actual short position data on the company info page.
