Some options available to people with Thunderbolt & USB 2.
USB-2 is 350 Mbps
USB-3, Thunderbolt and Firewire are 800 Mbps and higher.
Thunderbolt 2 drives and Firewire drive cases and docking stations are very hard to obtain.
LaCie made a Thunderbolt 2 to 2.5" SATA hard drive that you can get on eBay.
TripLite and Belkin have USB-3 to SATA and Parallel ATA hard drive adapter, but on an older Mac with USB-2 you will only get USB 2 speeds with this. Make sure to get one with an AC/DC power adapter. They are around $40.
So don't be surprised if the speed of data transfer is slow if it works at all. Don't try to multitask much while you do the data transfer. And turn off Energy Saver put hard drives to sleep, and don't close the lid of the laptop while it works. Use Screen Saver instead of Energy Saver.
It might be best if you upgrade your Mac's built-in hard drive to an SSD first and setup the OS as a clone there, and then try the data transfer from the old Macs. Platter drives make the final end of the transfer very slow.