Agilent 34401A K101 Relay Replacement

[rubidium]

This topic has been reviewed here a lot before, so I won't go into all of the detail. In summary, it has to do with drift in the 2W resistance measurement attributed to a failing K101 relay. The original part is essentially unobtanium by an individual from Keysight even if one is willing to pay their insane price, but in this post:
https://www.eevblog.com/forum/repair/agilent-34401a-2w-drift-and-high-readings-when-power-up/msg1346379/#msg1346379
it was suggested to use the COTO 3540-05-911. I made such a swap about a year ago with a 34401A and the repair was quite successful, but now I own another unit that is displaying the same problem. The issue is that even the 3540-05-911 isn't to be found anywhere, as it's essentially obsolete.  However, Newark has the COTO 3501-05-511 for only $15 !!

The differences among all of these appears to be as follows: The OEM part had a contact rating of 1000V, and the COTO 3540-05-911 has contacts rated at 500V. The 3501-05-511 has contacts rated at 200V. However, the latter also has a factor of 10 lower thermal EMF rating (<0.5uV, which should make it better), as well as a factor of 5 greater life expectancy (5E8 cycles). All of these have the same form factor and pin arrangement, so they will all be a simple drop in replacements. Should I be concerned with the lower contact voltage ratings? I don't see how anywhere near these voltages enter the 2W resistance measurement. But, of course, I may be missing something.

Thanks,
Jim