The phrase "a solid supply" is correct and usable in written English.
It can be used to describe a reliable and sufficient amount of something, often in contexts related to resources or inventory.
Example: "The warehouse has a solid supply of materials to meet the production demands for the upcoming quarter."
Alternatives: "a reliable supply" or "an ample supply".
Barker said: "The green deal has very solid foundations, and a solid supply chain.
Below I've recommended a corn concoction, for when there are the last ears in the markets or a solid supply in your freezer.
Even with a solid supply of Family Guy episodes on my iPod and a great book, the flight to Phoenix seems every bit the five hours that it is.
They had a solid supply of sleeping bags, air mattresses, tarps and tents, and inside the tents some of the camping enthusiasts were drinking, getting high, and so I heard fucking each other.
This series of events, combined with harassing tactics, confused the Federal authorities, causing them to fear that they did not have an adequate supply line to conquer the state and soon diverted from a course towards the capital and instead moved to Helena to reestablish a solid supply line.
While the results for the quarter were solid, supply chain issues for its 28nm chipsets caused Qualcomm to give a subdued forecast for the next quarter.
But I'm willing to bet most organizations' most effective managers have it in solid supply.
She estimates that the hundreds of cases she has seen are divided about equally between the two categories but laments that there are no studies to supply a solid answer.
When the press release said it would be available in 57 countries I believe this gave a solid indication that the supply of them would be better than what others were expecting.
Such feature spaces supply a solid basis for accurate predictions as they allow to capture complex relationships (e.g. binding site requirements).
In Danny Alexander, the Lib Dems have supplied a solid chief secretary to the Treasury and in Mr Cable, formerly of Labour, an improbable, yet more or less willing, collaborator.
