Your search for "radiometric mass flowmeters" revealed the following:

Endress+Hauser Flowphant T DTT31 compact thermal flow switch for liquid flow monitoring
Endress+Hauser Flowphant T DTT31 Compact Flow Switch
$720.00
No reviews
Yokogawa EJX910A multivariable transmitter
Yokogawa EJX910A Multivariable Transmitter
$610.00
No reviews
Yokogawa EJX930A multivariable transmitter
Yokogawa EJX930A Multivariable Transmitter
$610.00
No reviews
Endress+Hauser Prosonic FDU91 ultrasonic sensor for non-contact level and flow measurement
Endress+Hauser Prosonic FDU91 Ultrasonic Level Sensor
$1,000.00
No reviews