oldr was created for the simple purpose of allowing users of old versions of R to install the latest available versions (on CRAN) of R packages compatible with their version of R.
If you have devtools, you can install via
library(devtools)
install_github("duckmayr/oldr")If you don't, you can download or clone the repository, then use R CMD build oldr and R CMD INSTALL oldr_0.1.0.tar.gz
(For more details on installing the package from source if you don't have devtools, see, e.g., this page)
Once the package is installed, you just need to run
oldr::install.compatible.packages("package_name")to install a package named package_name.