Yes. The built-in self-timer should normally be enough to avoid shake from pressing the shutter. If you're still getting blur after a 2-second delay, the more likely problem is tripod stability rather than the lack of a remote release.

A simple DIY workaround is to use a lens cap or a piece of dark cardboard as a manual shutter for long exposures: set a long exposure, start it with the self-timer, let any vibration settle, then uncover the lens for the actual exposure time and cover it again before the shutter closes. This avoids adding vibration at the start of the recorded exposure.

So the practical options are:

• use the self-timer
• improve tripod/support stability
• for long exposures, use a cardboard/lens-cap "shutter" technique

For telephoto and astrophotography, support stability is critical.