Parse and convert string SNMP input

My SNMP provides some data in strings instead of floats:
$ snmpget -v1 -Cf -c public 192.168.0.2 NAS-MIB::systemFreeMem.0

NAS-MIB::systemFreeMem.0 = STRING: “7519.2 MB”

Is there a way I could parse this data ?

I have checked ‘converter’ plugin (https://github.com/influxdata/telegraf/tree/master/plugins/processors/converter)
as well as SNMP ‘conversion’ field parameter but those assume that string is a numeric value.

I am looking for something like regex input like:
https://docs.cacti.net/manual:088:3a_advanced_topics.3b_snmp_data_query_walkthrough#value_regexp_in_action

Unless you have other suggestions ?

The best you could probably do today is use the regex processor to remove the " MB" section, and then use the converter to convert the remaining numeric string to a float. However, I worry that you might still have an issue if the units can change.