Measuring Floating Measurements

I need to probe the voltage at the input of a high frequency (68 kHz) switch mode power supply transformer. This voltage is approximately 400 V PTP and is floating (not referenced to ground). Are any of the Velleman portable scopes capable of making this measurement?

Our lab scopes all have inputs referenced to ground and as such are not suitable for this type of measurement.

Thank you in advance for your support.

If the scope is battery operated it can make floating measurements, however, all Velleman scopes are CAT I instruments, so measurements are limited to 600V above ground.