Yes, IPv4 addresses are still available on the after-market (so to be purchased) via a transfer from company A to company B. The supply of IPv4 space on the market is getting tougher these days given the rising scarcity. So if you have plans and want to budget for this or next year, make sure that you reserve enough to last your expected need. It's expected for IPv4 addresses prices to rise so plan ahead and make sure to get the space you need in time.