Someone correct me if I am wrong, but with $700,000 and just one seed I believe you could mutate darn near any seed in the game if you know how mutation works.
perhaps the chart tool in
Virtual Seed Tray might help you to visually see which seeds you do have that are good candidates for mutation.
my advice would be to take the seed on the chart that is closest to the seed you want, cross breed it with itself to makes 11 plants. use mutation liquid on 10 of the plants to get a plant that is closer on the chart than the original plant. then take that plant, cross breed it with itself to make 11 plants, then mutate 10 of them to get a plant yet even closer on the chart to the seed you want. mutating 10 at a time you have a very small chance that statistically you won't get a plant that is in the correct direction on the chart, which is why you saved the 11th seed to cross breed with itself to make 11 more to try again.
if you are not sure what seed is closest or how mutation works, download Virtual Seed Tray and post a copy of your chart and I (we) will gladly suggest what to do. with $700,000 you really should be able to make any seed you want with very little trouble.