Question: I tried to sync the blockchain and, though I have ample free disk space (>500 GB on my computer, the chain is ~265) I've been having a hard time. So, how can I use an SPV node to send transactions and/or view the blockchain?

NOTE: don't do this if you don't have to because the blockchain needs nodes to ensure adequate distribution.

Answer: 
Try Electrum. Exact details on how to install depend on Linux distribution used.

Also Wasabi Wallet could be good choice, easy to setup.
Since your constraint is the blockchain size, it seems you would be fine with running bitcoind with `--prune` enabled to something like 2gb or similar. This is technically not an SPV solution, but you would have access to the bitcoin-qt gui ( if that's the version of bitcoind you have installed ) and you'd be able to run with your minimal constraints.