Well, we also sent them Shermans. And the UK provided a few (466) Churchills.
“Most visibly, the United States provided the Soviet Union with more than 400,000 jeeps and trucks, 14,000 aircraft, 8,000 tractors and construction vehicles, and 13,000 battle tanks”
So we sent 13000 tanks. Keep in mind that the USSR produced 60000 T-34s. So we provided almost of 18% of the Soviet medium armor. I would say that was ‘substantial.’
So we sent 13,000 tanks/SP, the Soviets produced 89,800 medium and heavy tanks/SP.
For aircraft, we sent 14,000 and the Soviet Union produced 136,200.