... Just to see how far she will push.  

 
Of course it would be insane to spend more on a pair of panties that the pussy they will covered is worth.  You don't put a $50,000 car cover on an $18,000 Hyundai.

 
But if I was feeling especially devilish, I might promise to buy them, then tell her I accidentally sent them to my home address ("Hey I'm always flustered by these interwebs thingies, Babe! Maybe you can teach me how to look up my accounts?). Then ask for her address so I can send them to her.  If I get it, I'll go to Shein online (known for cheap sexy women's clothes) and buy a $3 pair and ship.  

 
Once it gets delivered, hilarity ensues!  

 
Life is good

 
The Cat

of mine about the thong when I was a newbie at seeing a provider. I ripped her thong during the session. Afterward, she slipped the ripped thong into my coat pocket after our last kiss goodbye and whispered in my ear for a new one when I come next time. Short story, I learned quickly not to rip any thongs after, especially Agent Provocateur or La Perla. lol

To follow up:
After I refused to buy the $325 panties she made an offer for a $60 pair, but by then I decided I'd had enough.
I was ready to go to a local shop and buy something for $40 or $50 but it irks me to have a gal ask for a very specific thing like that. It seems like she values her panties more than the relationship.

She wanted you to mail them. Talked to the Same one in DC.

She has no interest in meeting, I don’t think.

The act of making a purchase ahead of a meet up can induce a mental momentum to go thru with sketchy last minute demands. Like, now she wants this thing I don't like but I've already committed this purchase so what the heck.  
.
Also someone collecting underpants (besides the underpants gnomes) might be either returning them for a refund (although many places don't accept returned under garments) or reselling them at a discount.