Used 6"@14 kHz coil covered with stone protector, this coil requires no cover. I haven't been using it more than 2 years since I bought 6"x10"@20 kHz. It fits AKA Signum MFT, AKA Signum MFD, AKA Sorex Pro and AKA Berkut 5.
Payment via paypal (personal payment). Price includes free shipping (EMS Post) and no shipping insurance.
In order to avoid customs formalities at destination, coil could be declared as a "gift"