microcontroller for OLED display

Hi,

None of the MSP430 devices contain an internal OLED driver, so you will need to use an external one. Depending on the driver you use, you will most likely need a serial connection (most likely SPI, but it could be others) to the driver, so this will partly determine what device you want. In general, when looking for an inexpensive device with a small pinout count, I suggest you start by looking at the MSP430FR2000. I do not know how much RAM you consider "decent," but you could also use the MSP430FR21xx devices, which will provide more memory (keep in mind these devices contain FRAM in addition to a small amount of RAM).

Regards,
Nathan

Point of terminology: Each of the OLED boards in the page you linked already has what is usually termed a "controller" -- e.g. SSD1306 -- on it, which deals with the electricals and logic of the raw screen and presents you a well-defined serial (SPI, I2C) and/or parallel (6800/8080) interface. What you're describing is an MCU (+firmware) to talk to the OLED "controller"; unfortunately, I don't know any succinct term for that.

Some considerations:
1) The SSD1306 can talk serial and parallel, but over different wires, so be sure the board has the wires you need. [You seem to have already done this.]
2) For parallel, your life will be much easier if you make sure your MCU has a full 8-pin port (e.g. P2.0-P2.7) available for the (8-bit) data bus with no conflicts. What can happen is you end up discovering that you also need e.g. a UART, and the only pin access is in the middle of your chosen data bus port. This consideration might push you to a larger MCU.
3) There is an advantage to being able to keep a full screen image in memory (SRAM/FRAM) all at once. For larger screens, this might be infeasible, but one of these screens in monochrome "only" needs 128x64/8=1KB. This might push you to a larger MCU.
4) Fonts (for text) take up space (Flash/FRAM). Be sure to budget for them. This might push you to a larger MCU.

As NathanS said, the FR2/4 series have a lot going for them, but you'll probably want the higher end of the line, e.g. FR4133.

[Edit: I goofed -- the FR2433 doesn't have the I/O you'll want.]