Since you have a MacBook, which come in hard disk sizes like 256GB, 512GB, 1TB, etc., if you don't have enough space to download the whole blockchain at once (you need about 300GB) or your internet plan won't let you download that much data in a month, then I would take the second option listed here and export the private keys.
You can either resync core or export the private keys which hold the balance.
You could fore example dump the whole wallet (dumpwallet in the command line) and then import every private key into a electrum wallet (or any other lightweight client which doesn't require the whole blockchain).
1- open your wallet in bitcoin core.
2- Go to the Console.
I believe it's under the Help menu, but I'm sure it's located inside the rightmost menu. It's under Window > Console
3- You might have to unlock the wallet first by entering your password, using
walletpassphrase PASSWORD 300 (decrypts your wallet with the provided password for 300 seconds, or 5 minutes.
4- Type
dumpwallet "/path/to/output/file/you/want.txt". This exports your private keys to a human-readable file.
5- Download and verify Electrum using the instructions here:
How to verify your Electrum [Windows, Linux, Mac].
6- Install and open Electrum and create a new wallet. Select "Import bitcoin addresses or private keys".
7- Open the text file where you dumped the private keys to, and paste them into Electrum. When you are done, delete this file as it's a security risk to leave the private keys exposed in a text file. Follow the remainder of the steps to create an Electrum wallet with your private keys.
