$90? Good job!
I just went through this with my 1974 Paramount P13-9. Low miles, but the original tubular tires were toast. At first, I wanted to get a separate wheelset with clinchers for riding. But checking my parts inventory, all of the wheelsets I have on hand have 27-inch rims. The brake set-up on my P13-9 requires 700C rims.
To do it right, I would need to purchase several items -- rims, 14-22t rear cluster, spokes, rear axle (I have a correct front axle), and probably new clincher tires. This added up to substantial cost. I wanted the bike done for an upcoming event, so I didn't have a lot of time to look for a complete, reasonably priced wheelset.
Then I asked myself, "How much will I ride this bike?" It's a wallhanger or show bike mostly; I likely won't ride it more than once per year. So then I got to thinking it would be nice to preserve the original configuration of the bike, even though I have reservations about tubulars.
I was a bit shocked by the cost of tubular tires, too. Dugast tires with silk casings go for at least $165 a piece. I think I remember another European brand for around $120 per tire. My LBS carried two Continental tubulars, one at around $70/tire and another at around $45/tire. Because I was running short on time and because I had never installed tubulars (I hear it's messy and tricky), I bought the better Contis from my LBS and had the tech there install them. They did a great job, and they appreciate classic road bikes. One of the techs was amazed at the lightness of my 1974-era bicycle!
This option worked for me because I have a '73 Paramount P10-9 with clinchers that is my "rider". If you have compatible clincher wheels or can get them cheaply, use those. If you want to replace the tubulars, I recommend going with the $70 Contis. I don't have a lot of miles on mine, so I can't comment on durability. Perhaps some of the others here who have experience riding tubulars can help with that.
P.S. My LBS owner recommended that I keep one of the old tubular tires (only one of mine still held air) as a spare. Back in the day, riders would tie a deflated tubular under the seat. He claimed I could throw it on the rim in an emergency, pump it up, and use it to ride home, as long as I was careful in the turns.