The only one I can find is the GWS 5000, I would not expect it to be cheap.
The device requires GPS so that it can report it’s location, with EIRP(effective isotropically radiated power) and other information which changes from country to country when requesting spectrum. Then it needs continuous internet access to contact the correct TV White Space Database server which would be different for each country, using the correct protocol for that country to negotiate a slice of spectrum to use for a short period of time (Ofcom granting use for up to 2 hours in the UK - https://tvws-databases.ofcom.org.uk/ , FCC granting use for up to 48 hours in the US - https://www.fcc.gov/general/white-space-database-administration and https://apps.fcc.gov/oet/translator/ ). I would have expected them all to have been using PAWS(Protocol to Access White-Space - RFC7545) databases, but every country can do it their own unique non-standard/individualistic way. I can see creating hardware as being the easy part, but getting it certified and complying with all the different legal requirements in each country would be very expensive. And then developing the software that can interact with many non-standard databases for access, I’d see as a total nightmare. Legally TX would need to be fully disabled until allocated spectrum, and then if you fail to renew your existing allocation, you would need to follow each countries individual policy requirements, which can and will change!
e.g. For Canada the “WSDB failure to access ISED database” procedure would be:
"Should the ISED database not be available, additional attempts to retrieve information from the ISED database shall be made at least once every 4 hours. If more than 12 hours has elapsed without the WSDBA being able to retrieve this information, the WSDBA shall contact ISED regarding the unsuccessful access to the ISED database.
Thereafter, a WSDB may continue to operate for 7 days, from the last successful access, unless otherwise indicated by ISED. After those 7 days, the WSDBA shall only operate in accordance with instructions provided by ISED. It is anticipated that the latter approach (i.e. contacting ISED for further instructions) would only occur in rare circumstances."